combustible
kum-BUS-tuh-bul
/kəmˈbʌs.tə.bəl/
Able to catch fire and burn easily; explosive or easily excited emotionally.
Describes materials that burn under normal atmospheric conditions when exposed to an ignition source.
The story behind the word. Traced back to Late Latin combustibilis, derived from Latin comburere (to burn completely), merging com- (intensive) with burere (to burn).
Word relationships
- flammable: Flammable materials ignite almost instantly, while combustible materials may require higher temperatures to catch fire.
- burnable: Burnable is informal, whereas combustible is formal and regulatory.
- incombustible: Incombustible means completely incapable of catching fire.
- fireproof: Fireproof describes items specially treated to resist fire.
Commonly confused with
- inflammable: Inflammable actually means highly flammable, despite the misleading prefix in-.
Word family
- combustion (noun): The process of burning something.
- combustibility (noun): The property of being capable of burning.
Collocations
- combustible material
- combustible gas
- combustible mixture
Example sentences
- "Store all combustible materials far away from open flames and electrical outlets." Safety Warning Label
- "The political tension in the crowded courtroom created a highly combustible environment." Figurative Narrative
Memory hook
Things that are COMBUSTIBLE will burn on a BUS. Combustion-ready bus.
When not to use
Do not confuse with flammable; while both mean capable of burning, flammable usually refers to materials that ignite instantly at low temperatures.
Fun facts
- In safety regulatory codes, 'flammable' liquids ignite below 100°F (37.8°C), while 'combustible' liquids ignite above that threshold.
Related words
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